非晶硅薄膜的激光晶化及深度剖析喇曼光谱研究  

Raman Depth Profile Research of Laser Crystallized a:Si Film

作　　者：徐晓轩[1] 林海波[1] 武中臣[1] 李洪波[2] 俞钢[3] 朱箭[1] 张存洲[1] 张光寅[1] 

机构地区：[1]南开大学光子学中心,天津300071 [2]南开大学光电子器件与薄膜研究所,天津300071 [3]美国Dupont公司,南开大学讲座教授天津300071

出　　处：《发光学报》2003年第4期426-430,共5页Chinese Journal of Luminescence

基　　金：教育部振兴计划资助项目

摘　　要：利用共焦显微喇曼光谱仪,对采用PECVD方法制备的非晶硅薄膜进行了退火晶化。晶化后薄膜的喇曼光谱表明,薄膜由非晶硅结构转变为微晶硅结构,同时根据微晶硅结构的喇曼光谱的晶化峰位的移动,可以计算出晶化后微晶硅晶粒尺寸为5nm左右。在对晶化后的薄膜进行深度剖析喇曼光谱研究中,对光谱进行分峰拟合,根据晶化峰的积分强度和非晶峰的积分强度的深度剖析曲线,可以看出晶化程度最高的部分位于薄膜中央,也就是在薄膜上层和接近衬底底部材料结构仍是非晶硅结构,而位于薄膜中间的材料结构转变为微晶硅结构。Using the backscattering geometry micro Raman microscopy, the a:Si film which made by PECVD was crystallized, and measured by the same instrument. The laser power density was about 83×105W/cm2 when using 100× objective (N.A.=09) and 61×105W/cm2 when using 50× objective(N.A.=075) to crystallizing. The wavelength of laser is 6328nm (HeNe laser). Based on the confocal Raman spectrometer and depth profile method, we collected the series of Raman spectrum of silicon film that the focus laser spot located the different depth in the amorphous silicon film when processing the laser crystallization. Through the Raman Stokes peak and antiStokes peak of microcrystallite silicon film which have been lasercrystallized, we can calculate the maximum temperature of the amorphous silicon film was about 1 600K in the process of lasercrystallized. At the same position on the sample, reduced the laser power density to about 6×104W/cm2 (the laser of this power density can not effect the character of the microcrystallite silicon film ), repeating the Raman depth profile experiment and getting the series of Raman spectrum. After curvefitting these Raman spectrum of the lasercrystallized silicon film, the Raman spectrum mainly fit to five peak (crystal silicon peak about at 520cm-1, amorphous peak about at 480cm-1 and others three peaks), we got the area of crystal silicon peak and amorphous silicon peak which attribute the degree of lasercrystallized and we discover crystalline phase located only in the middle of thin film. According to the Raman shift of the peak of crystal silicon, we estimated the size of crystal grain was about 5nm. By this way, the nanocrystal silicon material in the thin film have been achieved, and the character of crystalline phase in lasercrystallized polySi thin films has been researched. 

关 键 词：非晶硅薄膜 激光晶化 深度剖析 喇曼光谱 共焦显微喇曼光谱仪 PECVD 退火晶化 制备 

分 类 号：O484.41[理学—固体物理]